The embodiments herein relate to drill-in fluids comprising nanoparticulates for consolidating subterranean formations while drilling.
Subterranean formations, particularly hydrocarbon-producing formations, may comprise intervals that are weakly consolidated. As used herein, the term “weakly consolidated” and all variants thereof refers to one or more portions of a subterranean formation that contains loose (or unconsolidated) particulates and/or particulates having insufficient bond strength to withstand the forces created by the production (or injection) of fluids through the formation during subterranean treatment operations. These particles may include, for example, sand, clay, rock, or other particulate solids formed from the subterranean formation.
Some subterranean formations may initially comprise weakly consolidated intervals or may become so due to drilling operations, pumping operations, and other such subterranean operations that may abrade the surface of the formation and cause the formation of particulates. Such operations may additionally exacerbate the formation of particulates in an existing weakly consolidated interval.
Weakly consolidated formations may contain substantial quantities of oil and gas, but recovery of the oil and gas is often difficult due to the movement of unconsolidated particles. The creation and movement of these particulates may impose limitations on the drawdown pressure within the subterranean formation. As used herein, the term “drawdown pressure” refers to the differential pressure that drives fluids from within the wellbore to the surface. Therefore, unconsolidated particles may limit the rate at which fluids can be produced from the subterranean formation.
One approach designed to prevent the movement of unconsolidated particles in a wellbore in a subterranean formation (or to “consolidate” or “stabilize”) is the use of gravel packing or frac-packing techniques. As used herein, the term “gravel packing” refers to a particulate control method in which a permeable screen is placed in a wellbore in a subterranean formation and the annulus between the screen and the formation surface is packed with gravel of a specific size designed to prevent the passage of unconsolidated particles from the subterranean formation (e.g., from a weakly consolidated interval) through the gravel pack screen, referred to as a “gravel pack.” As used herein, the term “frac-packing” refers to a combined hydraulic fracturing and gravel packing treatment. In frac-packing operations, a substantially particulate-free fluid is pumped through the annulus between the permeable screen and the wellbore at a rate and pressure sufficient to create or enhance at least one fracture in the formation.
In both gravel packing and frac-packing operations, consolidation of unconsolidated particles in the subterranean formation is performed after drilling the particular interval being gravel packed or frac-packed. As such, damage to the drilling equipment and creation of additional unconsolidated particles during drilling cannot be controlled. Additionally, unconsolidated particles may still escape the confines of the gravel pack and flow into the wellbore opening, limiting well productivity.
Another technique for controlling the movement of unconsolidated particles in subterranean formations involves treating the formation with a consolidating agent to facilitate stabilization of the unconsolidated particles to prevent them from migrating from the formation. Traditional consolidating agents may be ineffective at treating long interval wellbores, as they may disproportionally aggregate in the portion of the wellbore closer to the initiation point of the wellbore. Traditional consolidating agents may additionally be difficult to handle, may be ineffectively placed into a formation, and may result in permeability damage.